How the Searchable Text Layer Works

When a PDF consists of scanned images, the text you see on screen is not actual text — it's a picture of text. OCR analyzes each page image, recognizes individual characters, and generates a hidden text layer positioned precisely behind each word. The visual appearance of the page stays identical, but you can now select text, use Ctrl+F to search, and copy content to other applications. This is essential for scanned contracts, invoices, academic papers, and archived documents.

Skip-Text vs. Force OCR

The Skip existing text mode (recommended) detects pages that already have selectable text and skips them, only processing image-based pages. This preserves the accuracy of any existing native text. Force OCR re-processes every page regardless, which is useful when the existing text layer is inaccurate or was generated by a different OCR engine. For documents that mix native text pages and scanned pages, skip-text mode produces the best results.

Accuracy & Scan Quality

OCR accuracy depends directly on the scan quality. High-resolution scans (300 DPI or higher) with clear, straight text produce the best results. Low-resolution scans, skewed pages, or documents with complex backgrounds may reduce accuracy. The deskew and clean options in the settings panel can improve results on imperfect scans. If you need to redact sensitive text after OCR, or convert to Word for editing, those tools work best on OCR-processed files.